| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable semiconductor device in which the composite material and plate thickness of a heat sink are selected so that high thermal cycle resistance amount can be ensured by sufficiently reducing thermal stress generated in a solder junction portion, while ensuring high thermal transmission performance and conductivity with respect to the heat sink to be stacked on an upper surface main electrode of a semiconductor chip and solder-joined. SOLUTION: The semiconductor device has an assembly structure in which a conductive heat sink 4 is stacked on a semiconductor chip 3 mounted on an insulating substrate 2, the heat sink 4 is joined by solder to the main electrode surface of the semiconductor chip, and a wiring lead 5 is joined to the top surface of the heat sink. In this semiconductor device, the heat sink 4 consists of a composite material fabricated by impregnating aluminum into a particle molding of carbon, silicon carbide or a mixture thereof by a pressure casting method, and its plate thickness t is set at a range of 0.2-2 mm. Further, an Ni plating layer 7 is formed on the solder junction surface of the heat sink, and the heat sink is stacked on the top surface main electrode of the semiconductor chip 3 and joined by solder. COPYRIGHT: (C)2007,JPO&INPIT |
